The present invention relates to an anti-rolling device of a ball and socket joint. In a ball and socket joint, the ball can be rotated in every direction on the center point of the socket and the ball. However, when it is applied to a hinge of a rocket nozzle for changing the thrust direction, the rolling movement of the moving body coupled to a ball, i.e. nozzle should be restricted.
A method for controlling a flight vehicle is thrust vectoring that is a function for changing the direction of thrust generated from a rocket motor nozzle. For such thrust vectoring of the nozzle, a ball and socket joint is employed as a mechanical hinge.
Specifically, a rocket motor nozzle part is comprised of a socket mounted on the dome area of a combustion, chamber, a ball which is mounted on the socket in a way of being rotatable on the center point of the socket, a nozzle which is coupled to the ball. Between the circumference of the nozzle as a moving body and the fixing part, two actuators are mounted to achieve the thrust vectoring of the nozzle. Further, for controlling the omni-directional tilt rotational movement of the nozzle, an anti-rolling linkage is generally used, and as an example of such technique, a technique disclosed in U.S. Pat. No. 4,506,832 can be mentioned.
However, in order to constrain the rolling movement of the nozzle by practicing the above-mentioned prior art, the center of movement in the lower pin of the linkage should be in the horizontal plane of the nozzle which passes through the center of the ball in extended line, thereby it causes difficulty in placing the linkage. When the lower pin center is not in position, thrust vectoring could be realized by special algorithms, but the ball the some roll motion against the socket for omni-directional thrust vectoring.